<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script crossorigin src="https://unpkg.com/react@18/umd/react.development.js"></script>
    <script crossorigin src="https://unpkg.com/react-dom@18/umd/react-dom.development.js"></script>
    <script src="https://unpkg.com/babel-standalone@6/babel.min.js"></script>
</head>
<body>
    <div id="root"></div>
    <script type="text/babel">
        class Root extends React.Component{
            constructor()
            {
                super();
                this.state = {
                    isReady:true
                }
                
            }

            btnClick(Els)
            {
                this.setState({
                    isReady:!this.state.isReady
                })
            } 
        
            render()
            {
                let Els = "我没准备好";
                const {isReady} = this.state;
                if(isReady)
                {
                    Els = "我准备好了";
                }
                return(
                    <div onClick ={(Els)=>{this.btnClick(Els)}}>
                     <div>{Els}</div>
                    </div>
                )
            }
        }
        const root = ReactDOM.createRoot(document.querySelector("#root"));
        root.render(<Root/>)
    </script>
</body>
</html>